cc.director.getPhysicsManager().enabled = true;
// cc.director.getPhysicsManager().debugDrawFlags = cc.PhysicsManager.DrawBits.e_aabbBit |
//     cc.PhysicsManager.DrawBits.e_pairBit |
//     cc.PhysicsManager.DrawBits.e_centerOfMassBit |
//     cc.PhysicsManager.DrawBits.e_jointBit |
//     cc.PhysicsManager.DrawBits.e_shapeBit
//     ;